paul ryan, vice presidential nominee preparing for his own debate avoided giving details of the romney tax plan even when he was pressed. >> you haven't given me the math. >> well, i don't have the, it would take me too long to go through all the math. >> reporter: the president is in nevada tonight for what insiders call three days of debate camp at a resort outside of las vegas. they too are trying to lower expectations and believe accounts that the romney campaign is convinced debates are about moments. >> the idea that i am anti-immigrant is repulsive. >> romney will come armed with several one-liners. >> clearly, they have been practicing zirng angers and linr months. that's not what the american people are looking for. >> the president is being coached to be crisper and shorten his answers. the former democratic candidate says mr. obama need to avoid being irritable. >> he has to relax, show a little sense of humor. show why he is lookable. >> reporter: the debate wednesday night is set for 90 minutes and will be entirely on domestic issues. the first half on jobs and the economy. th